From: Elmar Stellnberger Subject: Re: [PATCH 01/12] Ext4: Fix extended timestamp encoding and decoding Date: Mon, 30 Nov 2015 15:46:06 +0100 Message-ID: <565C612E.70804@elstel.org> References: <20151120145422.18930.72662.stgit@warthog.procyon.org.uk> <3495329.crWmoA5ACn@wuerfel> <20151129024555.GA31968@thunk.org> <2872067.shHdUXoF07@wuerfel> <20151130141605.GA4316@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit To: Theodore Ts'o , Arnd Bergmann , David Howells , linux-afs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Deepa Dinamani Return-path: In-Reply-To: <20151130141605.GA4316@thunk.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On 30.11.2015 15:16, Theodore Ts'o wrote: > On Sun, Nov 29, 2015 at 10:30:39PM +0100, Arnd Bergmann wrote: >> The other large missing piece is the system call implementation. I have >> posted a series earlier this year before my parental leave, and it's >> currently lacking review from libc folks, and blocked on me to update >> the series and post it again. > > I assume that this also means there hasn't been much thought about > userspace support above libc? i.e., how to take a 64-bit time64_t (or > changing the size of time_t) and translating that to a string using > some kind of version of ctime() and asctime(), and how to parse a > post-2038 date string and turning it into a 64-bit time_t on a 32-bit > platform? > Arnd, I would just like to tell you how much I welcome your decision for a new __kernel_time64_t! As a time[64]_t is basically well defined counting artificial seconds since the epoch (1970-01-01 00:00) where every year divisible by four is a leap year that is for the meanwhile already sufficient to make use of your new type. I just think about the Mayan calendar application which I have implemented last year (Though I have not brought it to a publishable state yet). A single typedef should be sufficient to let it make use of time64_t (it directly uses this type as well as long long internally for its calculations rather than the glibc time format functions).